System of control.



N. W. STORER & A. J. HALL.

SYSTEM OF CONTROL.

APPLICATION FILED MAR. 18. 1914.

1,157,821 Patented Oct. 26, 1915.

Fab/d 600/7: orer and UNITED STATES PATENT OFFICE.

NORMAN W. STORER, OF PITTSBURGH, AND ARTHUR J. HALL, OF WILKINSBURG,PENNSYLVANIA, ASSIGNORS TO WESTINGHOUSE ELECTRIC AND MANUFACTURINGCOMPANY, A CORPORATION OF PENNSYLVANIA.

SYSTEM OF CONTROL.

Specification of Letters Patent.

Patented Oct. 26, 1915.

Application filed March 18, 1914. Serial No. 825,491.

' of its objects to combine certain hitherto separately operated membersin one piece of control apparatus and to provide means for actuating thesame.

Another object of our invention is to provide a control system embodyingmeans of the above-entitled character, whereby the cost of constructionand installation and the number of control apparatus members arereduced, and the operation of the system is rendered more economical andconvenient than heretofore.

Another object of our invention is to provide a suitable device forelectro-pneumatically controlling the operation of a certain controlapparatus, as hereinafter described.

Heretofore, the switching devices known in the art-as the reverser andthe fieldchange-over switch have commonly been constructed as separatemembers. As the respective names imply, the reverser is employed toreverse the connections of either the motor armature or the fieldwinding, usually the latter; and the field change-over switch isutilized to change from full field to normal field connections, and viceversa, for a Well known purpose. In consequence, field connections havebeen brought through both devices, Whereby an unnecessary complicationof circuits has been entailed.

According to our invention, we provide a single structure embodyinswitching means respectively having the auctions of a reverser and fieldchange-over switch and likewise being provided with other conductingmeans. whereby the said connections are simplified, and operation of thesystem becomes easier and less expensive. The combined structure isadapted to assume two positions in each of the forward-running andreverse-running directions. The first step in either direction serves todirectly connect or reverse the field winding connections of the machineor machines, and the second step serves to eliminate a portion of thefield winding 0r windings.

In addition, we provide an electrically controlled, fluid-pressureoperated mechanism for actuating the combined structure outlined abovethat comprises a piston adapted to reciprocate in a cylinder, and a pairof electro-magnetically actuated valves for admitting fluid pressure tothe respective ends of the cylinder when energized througha plurality ofinterlocking contact members that are disposed on the combinedstructure, with the exception of one contact member which is associatedwith a resistor switch, and that are adapted for suitable circuitconnections with a master controller. The contact members referred toare so arranged that, when one valve magnet has been energized throughthe master controller to actuate the reverser to a field-changingposition after the motors are connected in full series relation, and thecontroller is moved beyond its corresponding position, the first valvemagnet is deenergized and the second magnet is automatically energized,whereby the reverser is returned to its full field position before thetransition from series to parallel circuit relation of the motors iseffected. The return actuation is thus positive and reliable and is notdependent upon the use of springs or similar devices such as havesometimes been employed heretofore in control apparatus.

In the accompanying drawing, Figure 1 is a diagrammatic view of acontrol system embodying our invention, the actuating mechanism underconsideration being shown in section, for clearness, and Fig. 2 is achart of familiar form showing the sequence of operation of theswitches. Although, for illustrative purposes, we have shown ourinvention in connection with an old and well-known control system, itwill be understood that the invention is not restricted in its use toany one type of control system.

Referring to the drawing. the system here shown comprises asupply-circuit conductor which is marked Trolley; a pair of electricmotors having armatures marked respectively M and M and field magnetwindings marked respectively F and F; a plurality of main-circuitresistor sections, one of which may be short-circuited by a switch R andanother by a switch R a plurality of control switches of a familiar typeLs, M, P, S and G for efi'ecting the desired circuit changes; a mastercontroller MC and a master reverser MR for energizing the controlswitches through a suitable control resistor CR and adapted to assume aplurality of motor-accelerating positions a to g, inclusive; amain-circuit and control circuit apparatus marked Field changeover andreverser and having the combined functions implied by the name; anelectrically controlled, pneumatically-operated actuator 1 for theapparatus just referred to; and a suitable source FP of fluid pressurefor the actuator.

The general construction of the combined field change-over and reverseris preferably similar to that of the familiar controller drums, althoughthe .reverser is here shown developed into a single phase, forconvenience of illustration. The apparatus is adapted to assume twooperative positions in either direction from an imaginary off position,the first position in one direction corresponding to the forward runningosition and the first position in the opposite direction correspondingto. the reverse running position, the second position in either caseserving to change from 'full field to normal field connections of themotors, for a purpose well-known in the art.

The actuator 1 comprises a piston "2; a suitable cylinder or casing 3therefor; a pair of magnet valves 4 and 5 of familiar construction,which are normally closed to admit atmospheric pressure only to thecyl-- inder 3, and which are adapted, when energized, to open and admitfluid pressure from any suitable source, as the tank FP, to therespective ends of the cylinder; and an oscillating link 6 operativelya$ociated with the piston 2 and suitably secured to the fieldchange-oi'er and reverser, whereby rotative movement of the latter iseflected. The duplex'piston 2 may be of any suitable construction and,preferably, has the link 6 oscillatably mounted intermediate the ends ofthe piston. Assuming the actuator to be in the forward running positionas shown in the drawing,'the valves 4 and 5 being closed, the operationof the actuator may be described as follows: Upon'the energization ofthe coils 7 or 7", as hereinafter described, the corresponding valveopens, thus making'communication with the source FF and I admittingfluid pressure to the corresponding end of the cylinder, whereby amovement of the piston away from that end ensues. To stop such movement,it is merely necessary to deenergize the valve-magnet coil in circuit,whereupon the valve closes to release the cylinder pressure and arrestthe motion of the erative position.

The field change-over and reverser here shown has the several sets ofmain contact members for reversing the motor connecpiston at any desiredoptions and for changing the amount of field magnet windings in circuit,disposed on the upper portion of the structure, and has the auxiliary,control circuit contact members master controller to its position a, acontrol circuit is established from the trolley, through a conductor 8,control fingers 9 and 10which are bridged by a contact segment 11-aconductor 12, control resistor CR and conductors 13 and 14 to ground.Another circuit is established through a conductor 15, control fingers16 and l7which are bridged by a contact member 18 of the master reverserMRa conductor 19, control fingers 20 and 21which are bridged by acontact member 22 of the field changeover and reverserc0nductor 23 andthe. coil of the reversing valve 5, to ground,

thus energizing the reversing coil of the re verser, which is thereuponactuated to its reverse running position, designated as RFF, by theactuator 1, thecontrol cir cuit being broken at the contact member 22. Asimilar and readily traced set of circuits is employed to cause asimilar actuation of the reverser from the above-describedreversedrunning position to the forward position shown in the drawing.In position a, of the master controller, if the master reverser has beenthrown to its forward position, a circuit is established from theconductor 15, through control fingers 16 and 24 which are bridged bycontact member 25 of the master reverser, conductor 26, control finger27 of the field change-over and reverser, contact members 28 and 29,control finger 30, conductor 31, auxiliary contact members 32 of anoverload trip switch O,T., and the coil of the line switch LS toanegative conductor 33. The line switch is thus In positions I) and 0,the resistor switches R and R are respectively closed, thereby disposingthe motors in full series relation. Inasmuch as this method of operationis familiar to those skilled in the art, no further description thereofis deemed necessary. In position d, an energized contact member 34 ofthe master controller engages a control finger 35, whence circuit iscompleted through a conductor 36, control fingers 37 and 38 whichrespectively engage contact members 39 and 40 and conductor 41 to thecoil of the valve 4. The field changeover and reverser is thus moved tothe second or field-changing position, designated as FNF. It will beobserved that-the above-mentioned connections of the line switch coilare maintained throughout the movement of the reverser. When the re;verser is moved to its second position, by reason of the peculiar shapeof the maincircuit contact members 42 and 43, contact is broken withcontrol fingers 44 and 45, and

circuit is made with control fingers 46 and 47, respectively. Fingers 44and 45 are re spectively connected to one end of the field windings Fand F and the fingers 46 and 47 to intermediate points of the respectivewindings and, therefore, the full field connections of the motors areseverally changed to the normal field connections and a higher speed isobtained.

The new control circuits established in the normal field position of thereverser may be traced as follows: from the energized control segment28, control finger 48, conductor 49, stationary contact member 50, atpresent not connected, but that are adapted to be bridged by a contactmember marked R out, when the switch R opens to its lower position,conductor 51, control-fingers 52 and 21, that are bridged by the contactmember 22, and the conductor 23 to the coil of the reversing valve 5.

By reason of the above described arrangement of circuits, when, duringthe actuation of the controller from position 0! to position 6, thecircuit of the coil of the forward valve 4 is broken at the mastercontroller contact member 34 and the circuit of the coil of switch R isinterrupted at an adjacent contact member 53, the circuit of the coil ofthe reversing valve is completed through the contact member marked R outand the field change-over and the reverser is, consequently, returned toits full field position, before the transition of the motors to parallelcircuit relation is effected by the closing of switch G, the opening ofswitch S and the closing of switch P, as indicated in Fig. 2. The switchR is then closed and the reverser is again actuated to positions 7 andg, respectively, in a manner similar to that hereinbefore described.

It will be understood that an operation of the reverser similar to thatjust recited will occur when the apparatus occupies its reverse runningposition, designated as RFF, upon the movement of the master controllerMC to either of its positions (Z or g. 'It will also be understood thatthe actuation of the field change-over and reverser from the forward tothe reversed position, or vice versa, reverses the connections of thefield winding F and F through the medium of certain of the contactmembers located upon the lower end of the combined apparatus and thecorresponding control fingers, in a well-known manner, detaileddescription of which is not deemed necessary here.

We do not wish to be restricted to the particular circuit connectionsand arrangement of parts herein set forth, but desire that only suchlimitations shall be imposed as are indicated in the appended claims.

We claim as our invention:

1. The combination with an electric motor, of a controller'thereforcomprising a single switching device having main circuit connections forreversing the motor and for changing the field strength thereof, andelectro-magnetic actuating means dependent for energization underpredetermined conditions upon the position of said device.

2. The combination with a power-operated member, and electrical meansfor governing the movement thereof, of a switching device for electricmotors operatively associated with said member and comprising means forreversing the motors upon occupation of predetermined positions of thedevice and for also changing the motor field strengths upon occupationof other positions, and electrical interlocking means for automaticallybiasing said device to certain of said positions under predeterminedconditions of motor operation.

3. The combination with a plurality of motors adaptedfor-series-parallel operation, a poweroperated member, and electricalmeans for governing the movement thereof, of a switching device-for saidmotors operatively associated with said member and having initialpositions corresponding to forward and reverse running, respectively,and having corresponding subsequent positions that are also adapted forchanging the motor field strengths, and electrical interlocking meansfor automatically returning said device to the corresponding initialposition from either of said subsequent positions upon operation of themotors from series to parallel relation.

4. A controller for electric motors comprising a single switching deviceadapted to assume a plurality of positions in either a forward or areverse direction, the initial positions corresponding to forward andreverse running, respectively, and the subsequent positions being alsoadapted to change the amounts of the motor field windings in circuit,and controllable electro-mechanical means for controlling said device.

5. A controller for electric motors com prising a single switchingdevice having circuit connections for reversing the motors and forindependently changing the field strengths thereof, and an actuatingmeans forsaid device comprising a movable member attached thereto, apiston operatively connected to said member, means for admitting fluidpressure to opposite sides of said piston, and electrical means forcontrolling the pressure admission.

6. The combination with a controller for electric motors comprising asingle switching device having main circuit connections for reversingthe motors and for changing the field strengths thereof, of anelectrically controlled actuating device for said controller, and aplurality of contact members disposed thereon for governing the circuitsof said electrically-controlled device.

7 The combination with a controller for electric motors comprising asingle switching device having main circuit connections for reversingthe motors and for changing the field strengths thereof, of anelectrically controlled actuating device for said controller, aplurality of contact members disposed thereon for governing the circuitsof said electrically controlled device, and an auxiliary apparatus forcontrollably supplying energy through said contact members to saidcircuits.

8. The combination with a controller for electric motors comprising asingle switching device having main circuit connections for reversingthe motors and for changing the field strengths thereof ofpower-operated means for actuating said controller, a pair ofelectro-magnetically actuatedvalves for respectively controllingmovement of said means in opposite directions, a supply circuit, anauxiliary controller, and a plurality of sets of contact membersdisposed onsaid switching device and arranged to govern the energizationof the magnet valve circuits from the master controller and the supplycircuit.

9. The combination with a supply circuit and a plurality of electricmotors, of a single switching device having initial portions, andprovided with circuit connections, for forward and reverse running,respectively, of the motors, and having corresponding subsequentpositions, and provided with circuit connections for changing the motorfield strengths, of fluid-pressure operated pistons for actuating saidcontroller, a cylinder in which the piston operates, a pair ofelectrically-governed magnet valves for respectively controlling theadmission and release of'fluid pressure on opposite sides of saidpiston, a master controller connected to said supply circuit, and aplurality of interlocking contact members disposed on said switchingdevice to govern the supply of energy from said controller to saidmagnet valves for producing a step-by-step movement of the switchingdevice in either direction.

10. In a control system, the combination with an electric motor, anaccelerating resistor, a plurality of motor-control switches, and amaster switch, of a switching device having circuit connections forreversing the motor and for independently changing the field strengththereof, and an electromagnetically controlled actuating means for thedevice.

11. In a control system, the combination with an electric motor, anaccelerating resistor, a plurality of control switches and a mastercontroller, of a switching device having a plurality of main andauxiliary con tact members, and an actuator for said device comprising apiston operatively connected thereto, a cylinder in which the pistonoperates, a pair of normally closed valves for controlling the admissionof fluid pressure to the respective ends of the cylinder, and electricalmeans dependent upon the positions of said master controller and saidauxiliary contact members for governing the valves.

12. The combination with a supply circuit and a plurality of electricmotors, of a single swltching device adapted to assume a plurality ofpositions in either a forward or a reverse direction, the initialpositions corresponding to forward and reverse running, respectively,and the subsequent positions being also adapted to change the amounts ofthe motor field windings in circuit, an actuator comprising a movablemember attached to said device, a piston operatively connected to saidmovable member, a cylinder in which the piston operates, a pair ofelectrically-controlled valves for admitting fluid pressure on oppositesides of said piston to produce a movement thereof in the one or theother direction, a master controller, and a plurality-of sets ofinterlocking contact members disposed and arranged on said switchingdevice to severally govern the electrical connections of said valves tosaid supply circuit, in conjunction with said controller, to selectivelyproduce movement of said device into any of its operative positions.

13. The combination with a'power-operated member, electrical means forgoverning the movement thereof, and an auxiliary circuit controller, ofa switching device for electric motors associated with said member andcomprising means for reversing the motors and for changing the fieldstrengths thereof, and means for controlling said elecineaear tricalmeans, whereby a predetermined movement of said power-operated member isproduced by actuation of said auxiliary circuit controller and wherebysaid member is returned to its initial position upon subsequentactuation of said controller.

14. The combination with a power-operated member, electrical means forgoverning the movement thereof, and a master controller, of a switchingdevice for electric motors associated with said member and comprisingcircuit connections for reversing the motors and for changing the fieldstrengths thereof and other circuit connections for controlling saidelectrical means in conjunction with said master controller, whereby apredetermined actuation of said controller energizes said electricalmeans to move said device to its field-changing position and wherebyfurther actuation of the-controller automatically energizes saidelectrical means to return said device to its original position.

15. The combination with a multi-position power-member, a pair ofmagnets for oppositely governing the movement thereof, and a mastercontroller, of a switching device operatively connected to said memberand having initial positions, and provided with circult connections forforward and reverse running, respectively, of the motors, and havingcorresponding subsequent positions, and provided with circuitconnections for changing the motor field strengths, auxiliary contactmaking means disposed on said device for energizing certain of saidmagnets in a predetermined position of said master controller to movesaid power-memher to its field-changing position, and means associatedwith another portion of the motor circuit for acting in conjunction withsaid auxiliary contacting means to deenergize said certain magnet andenergize the magnet to return said device to its initial position whenthe master controller is moved out of said predetermined position.

16. The combination with a supply circuit, an electric motor, aplurality of accelerating resistors, a plurality of short-circuitingswitches therefor, a plurality of actuating coils for said switches, ofa multi-position piston, an operating cylinder therefor, a pair ofmagnet valves for admitting fluid pressure to opposite sides of saidpiston, a switching device operatively connected to the piston andadapted to assume a plurality of positions in either a forward or areverse direction, the initial and normal positions corresponding toforward and reverse running, respectively, and the subsequent positionsbeing also adapted to change the amounts of the motor field windings incircuit, auxiliary contact making means disposed on said device forenergizing certain of said valve magnets in a predetermined position ofthe master controller to temporarily move said piston and said device tothe corresponding subsequent position, and interlocking contact meansassociated with one of the resistor short-circuiting switches forcompleting the circuit of the second valve magnet to return said deviceto its normal position when the master controller is actuated beyondsaid predetermined position to deenergize said first valve magnet andthe coil of said short-circuiting switch. In testimony whereof, we havehereunto subscribed our names this 27th day of Feb, 1914.

NQRMAN l V. STOREE. ARTHUR J. HALL.

Witnesses:

JACOB STAIR, J12, B. B. HINES.

